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Effects of Erosion Control Measures on Mountain Floods: A Case Study of the Censhui River South Branch Watershed
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作者 Changzhi Li Hong Wang +2 位作者 Baozhao Yuan Dongya Sun Changjun Liu 《Journal of Agricultural Science and Technology(A)》 2015年第8期646-654,共9页
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Heart Rate Variability, Standard of Measurement, Physiological Interpretation and Clinical Use in Mountain Marathon Runners during Sleep and after Acclimatization at 3480 m 被引量:5
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作者 Ivana Gritti Stefano Defendi +3 位作者 Clara Mauri Giuseppe Banfi Piergiorgio Duca Giulio Sergio Roi 《Journal of Behavioral and Brain Science》 2013年第1期26-48,共23页
Fluctuations in autonomic cardiovascular regulation during exposure to high altitude may increase the risk of heart attack during waking and sleep. This study compared heart rate variability (HVR) and its components d... Fluctuations in autonomic cardiovascular regulation during exposure to high altitude may increase the risk of heart attack during waking and sleep. This study compared heart rate variability (HVR) and its components during sleep at low altitude and after 30 - 41 hours of acclimatization at high altitude (3480 m) in five mountain marathon runners controlled for diet, drugs, light-dark cycle and jet lag. In comparison to sea level, RR-intervals during sleep at high altitude decreased significantly (P 0.001). The significant increase in sympathetic autonomic cardiovascular modulation at high altitude protects against excessive oxygen deprivation during sleep. Increases in R-R intervals can require longer periods of acclimatization at3480 m to mitigate the effects of altitude/hypoxia on sympathetic tone, thus reducing cardiovascular distress at rest during waking and sleep and probably before during and after athletic performance at altitude. 展开更多
关键词 Heart Rate Variability Very Low Frequency Fluctuation (VLF <0.04 Hz) RHYTHM Low-Frequency (LF 0.04 - 0.15 Hz) RHYTHM High-Frequency (HF 0.15 - 0.4 Hz) RHYTHM mountain MARATHON RUNNERS
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Performance assessment of two-dimensional hydraulic models for generation of flood inundation maps in mountain river basins 被引量:3
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作者 Juan Pinos Luis Timbe 《Water Science and Engineering》 EI CAS CSCD 2019年第1期11-18,共8页
Hydraulic models for the generation of flood inundation maps are not commonly applied in mountain river basins because of the difficulty in modeling the hydraulic behavior and the complex topography. This paper presen... Hydraulic models for the generation of flood inundation maps are not commonly applied in mountain river basins because of the difficulty in modeling the hydraulic behavior and the complex topography. This paper presents a comparative analysis of the performance of four twodimensional hydraulic models (HEC-RAS 2D, Iber 2D, Flood Modeller 2D, and PCSWMM 2D) with respect to the generation of flood inundation maps. The study area covers a 5-km reach of the Santa B-arbara River located in the Ecuadorian Andes, at 2330 masl, in Gualaceo. The model's performance was evaluated based on the water surface elevation and flood extent, in terms of the mean absolute difference and measure of fit. The analysis revealed that, for a given case, Iber 2D has the best performance in simulating the water level and inundation for flood events with 20- and 50-year return periods, respectively, followed by Flood Modeller 2D, HEC-RAS 2D, and PCSWMM 2D in terms of their performance. Grid resolution, the way in which hydraulic structures are mimicked, the model code, and the default value of the parameters are considered the main sources of prediction uncertainty. 展开更多
关键词 TWO-DIMENSIONAL HYDRAULIC models flood modeling flood extent Water surface ELEVATION High mountain RIVER Ecuador
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Theory and Application of Numerical Simulation of Chemical Flooding in High Temperature and High Salt Reservoirs
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作者 Yirang Yuan Aijie Cheng +1 位作者 Danping Yang Changfeng Li 《International Journal of Geosciences》 2014年第9期956-970,共15页
Applications, theoretical analysis and numerical methods are introduced for the simulation of mechanical models and principles of the porous flow in high temperature, high salt, complicated geology and large-scale res... Applications, theoretical analysis and numerical methods are introduced for the simulation of mechanical models and principles of the porous flow in high temperature, high salt, complicated geology and large-scale reservoirs in this paper. Considering petroleum geology, geochemistry, computational permeation fluid mechanics and computer technology, we state the models of permeation fluid mechanics and put forward a sequence of implicit upwind difference iteration schemes based on refined fractional steps of the upstream, which can compute the pressures, the saturation and the concentrations of different chemistry components. A type of software applicable in major industries has been completed and carried out in numerical analysis and simulations of oil extraction in Shengli Oil-field, which brings huge economic benefits and social benefits. This software gives many characters: spatial steps are taken as ten meters, the number of nodes is up to hundreds of thousands and simulation time period can be tens of years and the high-order accuracy can be promised in numerical data. Precise analysis is present for simplified models of this type and that provides a tool to solve the international famous problem. 展开更多
关键词 HIGH Temperature and HIGH SALT COMPLICATED Chemical floodING Computational PERMEATION Fluid Mechanics Numerical Method and Engineering Software Actual Application of Oil-Fields Theoretical Analysis
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Blood Chemistry, Acid-Base, Electrolyte, Blood Lactate Metabolism and Sleep at 3480 m in Mountain Marathon Runners
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作者 Ivana Gritti Clara Mauri +4 位作者 Stefano Defendi Daniele Cesana Federica Consonni Alberto Dolci Sabrina Luoni 《Journal of Behavioral and Brain Science》 2013年第1期13-25,共13页
Altered blood chemistry, acid-base and electrolyte are suggested determinants of sleep disturbance, with frequent arousal at high altitude even in well and long-trained altitude marathon runners. In this sample of exp... Altered blood chemistry, acid-base and electrolyte are suggested determinants of sleep disturbance, with frequent arousal at high altitude even in well and long-trained altitude marathon runners. In this sample of experienced altitude marathon runners with maximal aerobic power at sea level of 61.4 ± 2.7 ml/kg-1·min-1 we found that pO2 and percent of oxygen saturation (%SO2) were lower at2050 mand3480 mthan at sea level;pO2 was higher after 38 - 41 hours than after 30 - 31 hours of acclimatization at3480 m(P 2 decreased (P 2 and (P 2 at a sleeping altitude of3480 mwas lower (P Simple regression analysis disclosed a significant correlation between the changes in TST and the percent of REM sleep and the changes in %SpaO2 recorded during sleep (P 2 at higher altitude and the percent of W and of TST (P 2, tCO2 and [HCO3-] correlated negatively and significantly with the percent of REM sleep changes at high altitude (P 2 and pH and correlated negatively with the changes in %SO2, pCO2, tCO2, and [HCO3-] (P ++] and [BE] and negatively with the changes in buffered bases [BB] and [BEeffective] (P 2 and significantly and negatively with the changes in [K+] (P 2, tCO2, [HCO3-] and [K+] 展开更多
关键词 Clinical Investigation at High ALTITUDE Laboratory Investigation at High ALTITUDE Hematochemistry ACID-BASE METABOLISM Electrolyte METABOLISM Blood Lactate METABOLISM Hydration Status SLEEP Quality Indicators EEG mountain MARATHON RUNNERS
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Linguistic landscape and its impacts on place-making in mountain destination:A case of Mogan Mountain Town of Huzhou City,China
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作者 LI Chenyan LU Song +1 位作者 LONG Cheng ZHU Jiaheng 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1613-1629,共17页
The place and placeness are believed to be a crucial perspective for comprehending the transformative dynamics of tourist destinations in the context of globalization and the rapid development of the tourism industry.... The place and placeness are believed to be a crucial perspective for comprehending the transformative dynamics of tourist destinations in the context of globalization and the rapid development of the tourism industry.As the material carrier of language,linguistic landscape is an intermediary for people to endow emotions and personalities into the place,becoming an effective path for exploring the place-making in a certain area.Mogan Mountain is a famous national tourist resort,which is located in Mogan Mountain Town,Deqing County,Huzhou City,China.This is a good case area for studying the relationship between linguistic landscape and placemaking in tourist destinations.There are two theories that form the theoretical foundation of the study,namely the place and the geosemiotics.Firstly,the results showed the overall style of the linguistic landscape.Multilingual labelling(52.7%),official signs(55.3%),and standardized Chinese characters predominantly shaped the linguistic landscape,with English and other languages being complementary.Secondly,from the perspective of three dimensions of the geosemiotics framework,such as inscription,language preference,and placement position,we conduct a comprehensive semiotic analysis of the linguistic landscape,which encompasses diverse facets such as fonts,materials,shifts in state,text vectors,and symmetrical arrangements.Finally,we explore the influence of linguistic landscapes on the place-making of Mogan Mountain through the dimensions of location,locale,and sense of place.The information on linguistic landscapes indicates the geographical location.These linguistic landscapes play an important role in constructing the language order,nostalgic atmosphere,exotic atmosphere,and elegant and tasteful lifestyle of the public space in Mogan Mountain.Readers of linguistic landscapes,including tourists and residents,generate and identify with the unique sense of place in Mogan Mountain.These linguistic landscapes construct the destination placeness of Mogan Mountain that combines both foreign and nostalgic styles,and the integration of Chinese and Western cultures.It will help promote the image positioning of tourism destinations and have practical guiding significance for the tourism planning,landscape-making,language management,and other aspects of tourism destinations. 展开更多
关键词 Linguistic landscape PLACE-MAKING Tourist destination Geosemiotics Place theory Place branding Mogan mountain Town China
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安徽齐云山丹霞地貌成因 被引量:35
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作者 朱诚 彭华 +9 位作者 李世成 黄林燕 郑朝贵 项伏生 孙毓飞 唐云松 胡济源 朱光辉 吕健君 程光华 《地理学报》 EI CSCD 北大核心 2005年第3期445-455,共11页
齐云山丹霞地貌主要发育于中白垩统小岩组K2x1红色砂砾岩层中,该区地貌发育主要受景德镇-祁门断裂带、江湾-街口挤压破裂带和开化-淳安褶断带三大断裂带控制。在白垩世该区经历了地块沉降,成为陆上的断陷湖盆,由此接受了巨厚的白垩系红... 齐云山丹霞地貌主要发育于中白垩统小岩组K2x1红色砂砾岩层中,该区地貌发育主要受景德镇-祁门断裂带、江湾-街口挤压破裂带和开化-淳安褶断带三大断裂带控制。在白垩世该区经历了地块沉降,成为陆上的断陷湖盆,由此接受了巨厚的白垩系红层堆积。在新构造运动中,该区经历了隆升过程,巨厚的白垩系沉积物变成了海拔500 ̄600m的山体。白垩系红色砂砾岩在经历了垂直节理发育、风化破坏阶段及剥蚀搬运阶段后,同时受岩性本身砂岩与砾岩在组分和结构上的影响,差异性风化剥蚀显著,因此形成了壮观的峰林、崖、洞、方山、城堡及天生桥景观。该区585m、400m和150m处的三级裂点,大致反映了该区新构造运动中三次主要的抬升过程。 展开更多
关键词 500
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THE EARLY SUMMER FLOOD PERIODS OF SOUTHERN CHINA AND THE SUMMER MONSOON CIRCULATION OF EAST ASIA
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作者 黄士松 汤明敏 《Journal of Tropical Meteorology》 SCIE 1996年第1期12-16,14+18-25,共14页
THEEARLYSUMMERFLOODPERIODSOFSOUTHERNCHINAANDTHESUMMERMONSOONCIRCULATIONOFEASTASIA¥HuangShisongandTangMingmin... THEEARLYSUMMERFLOODPERIODSOFSOUTHERNCHINAANDTHESUMMERMONSOONCIRCULATIONOFEASTASIA¥HuangShisongandTangMingmin黄士松,汤明敏(Departmen... 展开更多
关键词 first flood of South China plum rains (Mei-yu ) period SUMMER MONSOON CIRCULATION of EAST ASIA establishment processes of the MONSOON CIRCULATION MONSOON regime structure
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Industrial Poverty Alleviation Model in Southwestern High-altitude Mountainous Areas of China——A Case Study of Industrial Poverty Alleviation of Xueshan Township in Luquan County of Yunnan Province through Planting Codonopsis pilosula 被引量:4
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作者 Zisheng YANG Renyi YANG +5 位作者 Yanbo HE Chonghui LU En ZHU Yaohan PI Mingxin WU Ying XIONG 《Asian Agricultural Research》 2019年第3期48-54,共7页
Due to the severe restrictions of natural conditions and ecological environment,high-altitude mountainous areas usually become the " hard bones" in the battle against poverty. Xueshan Township,Luquan Yi and ... Due to the severe restrictions of natural conditions and ecological environment,high-altitude mountainous areas usually become the " hard bones" in the battle against poverty. Xueshan Township,Luquan Yi and Miao Autonomous County of Yunnan Province,located in the alpine valley of Jinsha River,is a major township with wide and deep poverty,and the incidence of poverty is up to 45. 00%. In recent years,Xueshan Township has insisted on the battle against poverty,made effort to develop the Codonopsis pilosula industry,and successfully developed a road to poverty alleviation through C. pilosula industry,and formed a unique industrial poverty alleviation model by the end of 2018,the incidence of poverty dropped to 0. 74%. Based on field survey and interview,this paper analyzes and summarizes the specific practices,main results,practical experience and promotion and application measures of the poverty alleviation model of C. pilosula planting industry in Xueshan Township,in the hope of providing certain reference for the targeted poverty alleviation in similar areas in Yunnan Province and other provinces of China. 展开更多
关键词 HIGH-ALTITUDE mountainous areas INDUSTRIAL poverty alleviation Chinese herbal medicine PLANTING CODONOPSIS pilosula Model Xueshan Township of Luquan COUNTY
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阴山北麓地区植被覆盖动态时空分析 被引量:29
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作者 刘亚玲 潘志华 +1 位作者 范锦龙 郑大玮 《资源科学》 CSSCI CSCD 北大核心 2005年第4期168-174,共7页
阴山北麓地区是我国典型的生态脆弱带及北方重要的生态屏障,监测其植被覆盖变化是研究该地区以及农牧交错带对全球变化响应问题的基础与切入点.本文基于1998年~2003年该地区SPOT-4/VEGETATION的S10数据集,通过分析年均NDVI、年最大NDVI... 阴山北麓地区是我国典型的生态脆弱带及北方重要的生态屏障,监测其植被覆盖变化是研究该地区以及农牧交错带对全球变化响应问题的基础与切入点.本文基于1998年~2003年该地区SPOT-4/VEGETATION的S10数据集,通过分析年均NDVI、年最大NDVI、NDVI变化值、NDVI变化率等指标,得出:①全区年最大NDVI与全区年均NDVI具有可替代性;②1999年~2001年的全区年最大NDVI连续减少,而后两年连续增加,2003年情况与1998年基本持平;③林地、草地和耕地的年最大NDVI和年内变化幅度都是耕地>林地>草地,而6年间年最大NDVI变化幅度是林地>耕地>草地.2003年林地和耕地的年最大NDVI较1998年分别有微弱和较显著增加,而草地仍有较显著减少;④2001年较1998年的年最大NDVI除达茂旗中部、多伦县东部和商都县东南部少数地区有所改善外,其他大部地区呈现严重退化和显著减少;2003年较2001年除达茂旗西北部、多伦县东部零星地区呈现退化和减少外,其他所有地区都有中高度的改善和显著增加;2003年较1998年西北部有中度退化和显著减少,其他地区退化与改善并存. 展开更多
关键词 2003 1998 2001 NDVI 1999 西 退 S10
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Poverty Alleviation in the Poor Mountainous Areas of Western China by Supporting Industry: A Case Study of Xundian Hui and Yi Autonomous County in Yunnan Province
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作者 Bosheng ZHANG Zisheng YANG 《Asian Agricultural Research》 2019年第7期51-54,62,共5页
Poverty alleviation by supporting industry is a key measure to promote the poverty alleviation of relocated households. Taking Xundian County, the first county in Yunnan Province that has been lifted out of poverty, a... Poverty alleviation by supporting industry is a key measure to promote the poverty alleviation of relocated households. Taking Xundian County, the first county in Yunnan Province that has been lifted out of poverty, as an research case, this article analyzes and summarizes the industry-supporting poverty alleviation achievements and successful experience of two typical relocation areas (Shanhou Village and Eyang Village) in Xundian County. Practice has shown that the key to industry-supporting poverty alleviation lies in targetedness to strengthen the participation of poor farmers in industrial development. The interests of poverty alleviation entities should be linked by market mechanism to establish a benign interaction between all parties for win-win situation, thereby effectively guaranteeing the long-term and healthy development of poverty alleviation by supporting industry. 展开更多
关键词 Poverty-stricken mountainous area Targeted poverty alleviation by SUPPORTING INDUSTRY Relocation Model Interest linkage Xundian HUI and YI AUTONOMOUS COUNTY
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Experimental study of the effects of a multistage pore-throat structure on the seepage characteristics of sandstones in the Beibuwan Basin:Insights into the flooding mode
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作者 Lei Wang Xiao Lei +7 位作者 Qiao-Liang Zhang Guang-Qing Yao Bo Sui Xiao-Jun Chen Ming-Wei Wang Zhen-Yu Zhou Pan-Rong Wang Xiao-Dong Peng 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1044-1061,共18页
To investigate the relationship between grain sizes, seepage capacity, and oil-displacement efficiency in the Liushagang Formation of the Beibuwan Basin, this study identifies the multistage pore-throat structure as a... To investigate the relationship between grain sizes, seepage capacity, and oil-displacement efficiency in the Liushagang Formation of the Beibuwan Basin, this study identifies the multistage pore-throat structure as a crucial factor through a comparison of oil displacement in microscopic pore-throat experiments. The two-phase flow evaluation method based on the Li-Horne model is utilized to effectively characterize and quantify the seepage characteristics of different reservoirs, closely relating them to the distribution of microscopic pores and throats. It is observed that conglomerate sandstones at different stages exhibit significant heterogeneity and noticeable differences in seepage capacity, highlighting the crucial role played by certain large pore throats in determining seepage capacity and oil displacement efficiency. Furthermore, it was found that the displacement effects of conglomeratic sandstones with strong heterogeneity were inferior to those of conventional homogeneous sandstone, as evidenced by multiple displacement experiments conducted on core samples with varying granularities and flooding systems. Subsequently, core-based experiments on associated gas flooding after water flooding were conducted to address the challenge of achieving satisfactory results in a single displacement mode for reservoirs with significant heterogeneity. The results indicate that the oil recovery rates for associated gas flooding after water flooding increased by 7.3%-16.4% compared with water flooding alone at a gas-oil ratio of approximately 7000 m^(3)/m^(3). Therefore, considering the advantages of gas flooding in terms of seepage capacity, oil exchange ratio, and the potential for two-phase production, gas flooding is recommended as an energy supplement mode for homogeneous reservoirs in the presence of sufficient gas source and appropriate tectonic angle. On the other hand, associated gas flooding after water flooding is suggested to achieve a more favorable development effect compared to a single mode of energy supplementation for strongly heterogeneous sandstone reservoirs. 展开更多
关键词 Beibuwan Basin Multistage pore-throat structure Multistage seepage characteristics Microscopic visualization HETEROGENEITY Gas/water flooding flooding mode
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长江流域水汽收支与高原水汽输送分量“转换”特征 被引量:72
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作者 苗秋菊 徐祥德 张胜军 《气象学报》 CAS CSCD 北大核心 2005年第1期93-99,共7页
文中采用“箱体”模型边界的整层水汽输送特征描述长江流域梅雨带水汽收支总体效应 ,发现长江流域夏季降水与“箱体”模型整层水汽输送收支总量呈显著相关 ;青藏高原动力、热力强迫构成周边水汽输送特殊流型结构 ,大地形动力强迫导致高... 文中采用“箱体”模型边界的整层水汽输送特征描述长江流域梅雨带水汽收支总体效应 ,发现长江流域夏季降水与“箱体”模型整层水汽输送收支总量呈显著相关 ;青藏高原动力、热力强迫构成周边水汽输送特殊流型结构 ,大地形动力强迫导致高原周边水汽输送在高原南侧与东侧存在经向或纬向不同分量的水汽流型 ,且它们分别对长江流域梅雨带“箱体”模型水汽收支具有重要的影响。研究还发现高原南侧经向水汽输送与高原东侧纬向水汽输送分量之间呈显著相关特征 ,此研究揭示了长江流域洪涝过程上游高原周边关键区水汽输送不同分量间的“转换”特征 ,且此类水汽输送流型对夏季长江全流域各区域降水具有不同程度影响。上述高原周边水汽输送经向 纬向分量间的相互“转换”效应 ,是认识长江流域异常洪涝过程形成的关键环节之一。高原周边水汽输送分量相关结构及区域边界水汽收支问题将为长江流域洪涝预报提供科学依据。 展开更多
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造山带中成对出现的高压麻粒岩与榴辉岩及其地球动力学意义 被引量:48
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作者 张建新 于胜尧 +1 位作者 孟繁聪 李金平 《岩石学报》 SCIE CAS CSCD 北大核心 2009年第9期2224-2234,共11页
在一些典型碰撞造山带中,高压麻粒岩与榴辉岩在空间和时间上密切相关,它们之间的关系对揭示碰撞造山带的造山过程和造山机制具有重要意义。本文以中国西部的南阿尔金、柴北缘及中部的北秦岭造山带为例,详细陈述了这3个地区榴辉岩和相关... 在一些典型碰撞造山带中,高压麻粒岩与榴辉岩在空间和时间上密切相关,它们之间的关系对揭示碰撞造山带的造山过程和造山机制具有重要意义。本文以中国西部的南阿尔金、柴北缘及中部的北秦岭造山带为例,详细陈述了这3个地区榴辉岩和相关的高压麻粒岩的野外关系、变质演化和形成时代,目的是要建立大陆碰撞造山带中榴辉岩和相关高压麻粒岩形成的地球动力学背景模式。南阿尔金榴辉岩呈近东西向分布在江尕勒萨依-玉石矿沟一带,与含夕线石副片麻岩、花岗质片麻岩和少量大理岩构成榴辉岩-片麻岩单元,榴辉岩中含有柯石英假象,其峰期变质条件为P=2.8~3.0GPa,T=730~850℃,并在抬升过程中经历了角闪岩-麻粒岩相的叠加;大量年代学研究显示其峰期变质时代为485~500Ma。南阿尔金高压麻粒岩分布在巴什瓦克地区,包括高压基性麻粒岩和高压长英质麻粒岩,它们与超基性岩构成了一个大约5km宽的构造岩石单元,与周围角闪岩相的片麻岩为韧性剪切带接触。长英质麻粒岩和基性麻粒岩的峰期组合均具有蓝晶石和三元长石(已变成条纹长石),形成的温压条件为T=930~1020℃,P=1.8~2.5GPa,并在退变质过程中经历了中压麻粒岩相变质作用叠加。锆石SHRIMP测定显示巴什瓦克高压麻粒岩的峰期变质时代为493~497Ma。都兰地区的榴辉岩分布柴北缘HP-UHP变质带的东端,在榴辉岩和围岩副片麻岩中均发现有柯石英保存,形成的峰期温压条件为T=670~730℃和,P=2.7~3.25GPa,退变质阶段经过了角闪岩相的叠加;榴辉岩相变质时代为420~450Ma。都兰地区的高压麻粒岩分布在阿尔茨托山西部,高压麻粒岩包括基性麻粒岩长英质麻粒岩,基性麻粒岩的峰期矿物组合为Crt+Cpx+Pl±Ky±Zo+Rt±Qtz,长英质麻粒岩的峰期矿物组合为:Grt+Kf+Ky+Pl+Qtz。峰期变质条件为T=800~925℃,P=1.4~1.85GPa,退变质阶段经历了角闪岩-绿片岩的改造,高压麻粒岩的变质时代为420~450Ma。北秦岭榴辉岩分布在官坡-双槐树一带,榴辉岩的峰期变质组合为Grt+Omp±Phe+Qtz+Rt,所计算的峰期温压条件为T=680~770℃和P=2.25~2.65GPa,年代学数据显示榴辉岩的变质时代为500Ma左右。北秦岭高压麻粒岩分布在含榴辉岩单元的南侧松树沟一带,包括高压基性麻粒岩和高压长英质麻粒岩,与超基性岩在空间上密切伴生,高压麻粒岩的峰期温压条件为T=850~925℃,P=1.45~1.80GPa,锆石U-Pb年代学研究显示其峰期变质时代为485~507Ma。以上三个实例显示,出现在同一造山带、在空间上伴生的高压麻粒岩和榴辉岩有各自不同的变质演化历史,但榴辉岩中的榴辉岩相变质时代和相邻的高压麻粒岩中的高压麻粒岩相变质作用时代相同或相近,这种成对出现的榴辉岩和高压麻粒岩代表了它们同时形成在造山带中不同的构造环境中,即榴辉岩的形成于大陆俯冲带中,而高压麻粒岩可能形成在俯冲带之上增厚的大陆地壳根部。 展开更多
关键词 North Qaidam mountains area multistage metamorphism high thermal relaxation continental crust mafic GRANULITES Mineral
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A system-integrated approach for the design of tourist areas at the local level under changing conditions:A case study in the Altay Mountains
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作者 Alexandr Nikolaevich DUNETS Evgeniya Mikhailovna TABAKAEVA HAN Fang 《Regional Sustainability》 2024年第2期89-102,共14页
The existing approaches for the design of tourist areas often lead to limited flexibility in project implementation.To realize a more flexible approach,in this study,we formulated a model for planning and designing to... The existing approaches for the design of tourist areas often lead to limited flexibility in project implementation.To realize a more flexible approach,in this study,we formulated a model for planning and designing tourist areas at the local level.Moreover,specific tools for analyzing tourist areas and ensuring sustainable development under changing conditions were developed.This study was conducted in two tourist regions,Biryuzovaya Katun tourist complex and Belokurikha destination(including Belokurikha City with Belokurikha 2 Gornaya tourist complex and surrounding areas),in the Altay Mountains.We employed the recreation opportunity spectrum and proposed a system-integrated programming approach for the design of tourist areas at the destination and site levels.The key of this approach was the collection and analysis of current spatial data,including the spatial distribution of attractions and visitor flows.We constructed heat maps using video recording and unmanned aerial vehicle(UAV)observation data.Moreover,we analyzed the video stream using an image-analyzing framework You Only Look Once(YOLO)v5 software.The heat map of visitor flows based on video recording data in the Andreevskaya Sloboda museum of Belokurikha 2 Gornaya tourist complex allowed us to highlight the most attractive sites in this area and classify them into one of three types:points of functional concentration,points of transitional concentration,and points of attractions.The heat maps in Biryuzovaya Katun tourist complex,created using UAV observation data,allowed us to determine the spatiotemporal patterns of visitor flows and tourists’preferences throughout the day within four time intervals:09:00-12:00,13:00-14:00,14:00-15:00,and 16:00-18:00(LST).The maximum visitor flow density occurred from 16:00 to 18:00 in the beach area of the artificial lake.A comparison between the visitor-concentrated sites and the current facilities provided insights into the demand for attractions and facilities and the lacking areas.Heat maps are useful in analyzing the land use at the site level,while zoning based on the recreation opportunity spectrum can be used to design tourist areas at the destination level.The proposed methods for analyzing the use of tourist areas contribute to the development of adaptive tourism design. 展开更多
关键词 Tourism planning Tourist areas Unmanned aerial vehicle(UAV) Visitor flows Heat map Altay mountains
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GIS-based flash flooding susceptibility analysis and water management in arid mountain ranges:Safaga Region,Red Sea Mountains,Egypt
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作者 Ahmed E.EL-RAYES Mohamed O.ARNOUS Ahmed M.HELMY 《Journal of Mountain Science》 SCIE CSCD 2023年第12期3665-3686,共22页
The Safaga Region(SR)is part of the Red Sea mountain range in Egypt.Catastrophic flash flooding is now an inescapable event,wreaking havoc and causing massive loss of life and property.The majority of the floodwater,h... The Safaga Region(SR)is part of the Red Sea mountain range in Egypt.Catastrophic flash flooding is now an inescapable event,wreaking havoc and causing massive loss of life and property.The majority of the floodwater,however,has been wasted as runoff to the Red Sea,which,if used wisely,could meet a fraction of the water demands for a variety of applications in this area.The current work aims to use GIS techniques to integrate remote sensing data for evaluating,mitigating,and managing flash floods in SR.The data set comprised Tropical Rainfall Measuring Mission(TRMM)thematic rainfall data,1:50,000 scale topographical map sheets,geological maps,the ASTER Digital Elevation Model(ASTER GDEM),Landsat 7 Enhanced Thematic Mapper"(ETM7+),and Landsat 8 Operational Land Imager.The flash flood risk model of SR is developed using ArcGIS-10.3 geoprocessing tools integrating all the causal factors thematic maps.The final flood risk model for the SR suggests that 57%of the total basins in the SR are at high risk of flooding.Almost 38%of all basins are at moderate flood risk.The remaining 5%of basins are less prone to flooding.Flood-prone zones were identified,suitable dam-building sites were located,and extremely probable areas for water recharge were recognized.On the basis of reliable scientific data,structural and non-structural mitigation strategies that might reduce the damage susceptibility,alleviate the sensitivity of the flash flood,and best utilize its water supply were recommended. 展开更多
关键词 Flash floods GIS SUSCEPTIBILITY Water management Arid mountains EGYPT
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A Preliminary Study on the Rational Utilization of Land Resources in the Poverty-Stricken Mountainous Areas in the Upper Reaches of the Yangtze River:A Case Study of Xueshan Township 被引量:2
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作者 Jia WANG Leijin LONG 《Asian Agricultural Research》 2020年第2期17-24,27,共9页
As one of the most fragile alpine plateau and canyon areas in China,the upper reaches of the Yangtze River are the key areas of ecological construction in China.It is also a key area for poverty alleviation in the cou... As one of the most fragile alpine plateau and canyon areas in China,the upper reaches of the Yangtze River are the key areas of ecological construction in China.It is also a key area for poverty alleviation in the country.Therefore,it is necessary to take into account the dual goals of poverty reduction and ecological environment construction,and explore a win-win road of ecological construction and poverty alleviation in line with the reality of the upper reaches of the Yangtze River.Taking Xueshan Township,Luquan Yi and Miao Autonomous County,Yunnan Province,which is located in the poor mountainous area of the upper reaches of the Yangtze River as an example,based on many field investigations and existing investigation and statistical data,this paper analyzes the current situation and main problems of land use in Xueshan Township,and then puts forward measures and suggestions for rational utilization of land resources in Xueshan Township.This can provide a necessary reference for the next implementation of rural revitalization strategy and ecological construction. 展开更多
关键词 Land resources RATIONAL utilization UPPER reaches of the YANGTZE River POOR mountainous areas Xueshan Township Luquan COUNTY
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Ecological Restoration Technology and Benefit Assessment of Karst Rocky Desertification Mountains in Xixiu District of Anshun City
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作者 Li LAI Ying PENG +1 位作者 Yujie LIU Hongwei XING 《Asian Agricultural Research》 2019年第4期40-45,共6页
Ecological restoration refers to the containment of soil erosion,restoration of water conservation,climate regulation,maintenance of ecological functions of biodiversity,and improvement of ecological environment and l... Ecological restoration refers to the containment of soil erosion,restoration of water conservation,climate regulation,maintenance of ecological functions of biodiversity,and improvement of ecological environment and landscape pattern based on self-repairing capacity of the nature and combined with appropriate artificial measures. Since the natural restoration process of karst desertification mountain is very long,it needs to be supplemented by artificial vegetation restoration. This paper introduced the ecological restoration technologies implemented in karst rocky desertification mountains in Xixiu District,Anshun City of Guizhou Province,and also introduced the afforestation tending management measures. It assessed the ecological benefits of the ecological restoration project from five aspects: mountain community characteristics,vegetation coverage,species diversity,afforestation survival rate and landscape effect. 展开更多
关键词 KARST rocky DESERTIFICATION mountainS Ecological restoration Technical measures Benefit assessment Xixiu DISTRICT of ANHUI CITY in Guizhou Province
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Characteristics and displacement mechanisms of the dispersed particle gel soft heterogeneous compound flooding system 被引量:3
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作者 ZHAO Guang DAI Caili YOU Qing 《Petroleum Exploration and Development》 2018年第3期481-490,共10页
Considering high temperature and high salinity in the reservoirs, a dispersed particle gel soft heterogeneous compound(SHC) flooding system was prepared to improve the micro-profile control and displacement efficiency... Considering high temperature and high salinity in the reservoirs, a dispersed particle gel soft heterogeneous compound(SHC) flooding system was prepared to improve the micro-profile control and displacement efficiency. The characteristics and displacement mechanisms of the system were investigated via core flow tests and visual simulation experiments. The SHC flooding system composed of DPG particles and surfactants was suitable for the reservoirs with the temperature of 80-110 °C and the salinity of 1×10~4-10×10~4 mg/L. The system presented good characteristics: low viscosity, weak negatively charged, temperature and salinity resistance, particles aggregation capacity, wettability alteration on oil wet surface, wettability weaken on water wet surface, and interfacial tension(IFT) still less than 1×10^(-1) mN/m after aging at high temperature. The SHC flooding system achieved the micro-profile control by entering formations deeply and the better performance was found in the formation with the higher permeability difference existing between the layers, which suggested that the flooding system was superior to the surfactants, DPG particles, and polymer/surfactant compound flooding systems. The system could effectively enhance the micro-profile control in porous media through four behaviors, including direct plugging, bridging, adsorption, and retention. Moreover, the surfactant in the system magnified the deep migration capability and oil displacement capacity of the SHC flooding system, and the impact was strengthened through the mechanisms of improved displacement capacity, synergistic emulsification, enhanced wettability alteration ability and coalescence of oil belts. The synergistic effect of the two components of SHC flooding system improved oil displacement efficiency and subsequently enhanced oil recovery. 展开更多
关键词 SOFT HETEROGENEOUS COMPOUND flooding dispersed PARTICLE GEL surfactant synergistic effect DISPLACEMENT mechanism high temperature and high salinity reservoirs
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Comparison of oil displacement mechanisms and performances between continuous and dispersed phase flooding agents 被引量:2
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作者 SUN Zhe WU Xingcai +4 位作者 KANG Xiaodong LU Xiangguo LI Qiang JIANG Weidong ZHANG Jing 《Petroleum Exploration and Development》 2019年第1期121-129,共9页
To compare the oil displacement mechanisms and performances of continuous phase flooding agent(traditional polymer solution) and dispersed phase flooding agent(particle-type polymer SMG dispersion), the particle phase... To compare the oil displacement mechanisms and performances of continuous phase flooding agent(traditional polymer solution) and dispersed phase flooding agent(particle-type polymer SMG dispersion), the particle phase separation of SMG dispersion migrating in pores was simulated by using the microfluidic technology. Theoretically guided by the tree fork concentration distribution of red cells in biological fluid mechanics, the concentration distribution mathematical model of SMG in different pores is established. Furthermore, the micro and macro physical simulation experiments of continuous and dispersed phase flooding agents were carried out. The results show that the continuous flooding agent enters all the swept zones and increases the flow resistance in both larger and small pores. On the contrary, the particle phase separation phenomenon occurs during the injection process of dispersed flooding agent. The SMG particles gather in the larger pore to form bridge blinding, and the carrier fluid displace oil in the small pore. Working in cooperation, the SMG particle and carrier fluid drive the residual oil in the low permeability layers step by step and achieve the goal of enhanced oil recovery. The laboratory experimental results indicate that, the oil increment and water reduction effect of dispersed flooding agent is much better than that of continuous flooding agent, which is consistent with the field test results. 展开更多
关键词 POLYMER floodING particle-type POLYMER POLYMER water dispersion PARTICLE phase separation microfluidic technology deep fluid DIVERSION ability oil DISPLACEMENT mechanism
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